As part of the National Human Exposure Assessment Survey,
a multistage sampling was used to estimate and compare
exposures and risks associated with drinking water for two
groups - the population of Arizona and that of border communities.
There had been some concern that the border communities'
exposures would be higher than those of other parts of the state
because of their proximity to Mexico, where environmental quality
may not be as high a priority as it is in the United States.
The two study populations were further categorized by gender,
age, ethnicity, education, income, and building structure type and
year of construction. For these subgroups, the study estimated and
compared risks for arsenic, 1,3-butadiene, chloroform, chromium,
1,2-dichloroethane, dichloromethane, lead, nickel, and toluene. For
almost all of the sample subjects, residue concentrations were
below the drinking water guideline values of both Arizona and the
US Environmental Protection Agency. Of the metals studied,
arsenic was the only one with a population carcinogenic risk above
the acceptable level of 1.0E-6. Contrary to expressed concerns,
average daily exposures and associated risks were estimated to be
smaller in the border communities than in the Arizona population.
For utilities, one finding deserving further study was that risks
from tap water were estimated to be greater than risks from
nontap water. Further research may be warranted to uncover the
causes for these elevated risks. Includes 26 references, tables, figure.
| Edition : | Vol. 95 - No. 7 |
| File Size : | 1
file
, 370 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 13 |
| Published : | 07/01/2003 |
